Ichiro Amimori1
Xenoma Inc.1
<b>Introduction</b><br/>Xenoma’s e-skin is the next generation smart apparel that is comfortable, mechanically robust, well-insulated and machine washable IoT clothing. In order to place many sensors on fabric, we have developed printed circuit fabric (PCF) based on a novel stretchable electric circuit. For mass-production, it is not efficient enough to attach an electric circuit onto 3D shaped clothes since the process requires an alignment process to precisely locate insulation layers on wirings. We make PCFs and then sew it onto clothes. PCF enables us to freely design a smart apparel. PCF is an evolutionary version of a flexible printed circuit and can be used for making smart apparel.<br/><br/><b>e-skin Product Lineup</b><br/>We have a diverse range of e-skins. e-skin Sleep & Lounge comes in both loungewear and pajama types. In the daytime, e-skin Lounge can detect falls for elderly care. At night, e-skin Sleep can monitor sleep quality through parameters such as heart rate, respiration rate, body motion and sleep stage.<br/>e-skin MEVA is a smart motion capture suit, which can be set up more easily and post processes quicker than marker-based optical motion capture systems. 18 6-axis inertial motion unit (IMU) sensors are located on whole-body skeletal segments to measure and calculate posture and position of each segment. Users do not have to worry about where to put sensors on their body since the suit can automatically determine the sensors’ position on the body. e-skin MEVA is the easiest and quickest motion capture system in the world.<br/>e-skin EMStyle is an electrical muscle stimulation (EMS) full-body suit for training and rehabilitation. A trainer in a gym can connect with a trainee at home to control the trainee’s stimulation levels remotely online. It’s the only system in the world that can do this.<br/><br/><b>Basic System of e-skin</b><br/>Each e-skin system consists of apparel and electronics, specifically an e-skin Hub as a controller along with an application. The Hub contains a microcomputer, wireless transmitter module and battery. Sensor data is collected on the Hub and transferred wirelessly through a medium such as Bluetooth to your smartphone app, PC app, or directly to the cloud server. Since e-skin can easily obtain users’ healthcare data, e-skin can be considered as a healthcare big data platform.<br/><br/><b>Stretchable Wirings in e-skin</b><br/>Xenoma uses different stretchable wirings depending on the circuit design of the PCF. e-skin Sleep uses a thermally sensitive resistor to measure temperature in bed. The resistance of the wiring must be stable since resistance change directly affects measurement accuracy. IMU sensors in e-skin MEVA measures 3-axis acceleration and 3-axis angular velocity and that data is digitally transferred from stretchable wirings using the I2C communication protocol. All IMU sensors are connected with the Hub via 4 stretchable wirings including the data line (SDA), clock line (SCL), VCC and ground (GND), respectively. e-skin EMStyle is not a sensor system but one of the actuator systems using EMS. A current of about 200 mA flows through stretchable wiring and the full-body suit can stretch more than twice its size when worn. Therefore, the stretchable wirings in e-skin EMStyle must have a large robustness against being stretched.<br/><br/><b>Conclusion</b><br/>Xenoma has already established a mass-scale level of PCF technology and new electronics components for stretchable electronics will infinitely expand the possibilities of e-skin. PCF technology will also contribute to electronics in soft materials such as soft robotics.